Contoured Mesh Ridge Vents

ABSTRACT

Ridge vents and deck covers are disclosed that have a fibrous mesh mat and a moisture barrier. The mesh mat may be contoured to define a variety of structures and may have regions of relatively higher fiber density and regions of relatively lower fiber density. Solar cells may be exposed on the ridge vents to collect solar energy when the vents are exposed to sunlight.

REFERENCE TO RELATED APPLICATION

Priority is hereby claimed to the filing date of U.S. provisional patent application 61/740,085 filed on Dec. 20, 2012 and bearing the title Contoured Mesh Ridge Vents.

TECHNICAL FIELD

This disclosure relates generally to attic ventilation and more specifically to open weave mesh material that can be used to cover a ridge slot along the ridge of a roof or a hip slot along a hip of a roof to provide attic ventilation.

BACKGROUND

To ventilate an attic space, it is common to form a ridge slot in the roof deck extending along a ridge of the roof and to install a ridge vent over the ridge slot in conjunction with installation of soffit ventilation. For hip roofs, it is common to form a hip slot along a hip of the roof and cover the hip slot with a hip vent to provide ventilation. This disclosure will be couched primarily within the context of ridge vents for ease of explanation, but the invention is applicable to hip vents and indeed other attic ventilation devices. A ridge vent permits heated air from the attic below to pass by convection through the ridge slot and through the vent while preventing ingress of water, insects, and vermin into the attic. One common type of ridge vent is the so-called rollable mesh ridge vent. One rollable mesh ridge vent that has been commercially successful is the ridge vent and system disclosed in U.S. Pat. No. 5,167,579 of Rotter entitled Roof Vent of Synthetic Fiber Matting. This patent is hereby incorporated fully by reference. Generally, the Rotter ridge vent is a unitary sheet construction of randomly aligned synthetic fibers that are open and blended, randomly aligned into a web by airflow, joined by phenolic or latex binding agents, and heat cured to produce an air-permeable mat with a substantially constant fiber density throughout. The vent is fabricated in substantial lengths and is rolled into a roll for storage and shipment. For installation, the vent is unrolled along a roof ridge covering a ridge slot and secured to the roof decking on either side of the slot. Ridge cap shingles are then installed atop the ridge vent to form a moisture barrier and to present a traditional appearance. Warm air from the attic below passes through the ridge slot, flows through the mesh mat of the ridge vent, and exits along the edges of the ridge vent to ambience.

While the Rotter ridge vent has proven successful, it nevertheless suffers from certain inherent shortcomings. For example, the fibrous mat material of the Rotter ridge vent has a substantially constant fiber density throughout, and is air and water permeable throughout. Thus, ridge cap shingles are required to prevent water from penetrating through the mat and into the attic below. The Rotter ridge vent also has a constant thickness throughout, even though not all regions of the ridge vent require this thickness for the vent to function properly. There is thus a certain waste of material in such regions of the Rotter ridge vent. Centering the Rotter ridge vent across a ridge slot also can be imprecise since an installer generally centers the mat by eye, which can result in more of the mat on one side of the ridge slot than on the other side of the ridge slot. The Rotter ridge vent also lacks wind baffles found on more expensive injection molded plastic ridge vents, and such wind baffles can improve ventilation efficiency. These are only a few examples of shortcomings of the Rotter ridge vent.

Needs exist for fiber mesh attic vents and ridge vents in particular that address these and other shortcomings of traditional mesh ridge vents such as the Rotter ridge vent. It is to the provision of a variety of mesh-type ridge vent configurations that address these and other needs and that provide other advantages that the present invention is primarily directed.

SUMMARY

Briefly described, a plurality of mesh-type ridge vent configurations are disclosed that each provides certain benefits not currently found in commercial fiber mesh ridge vents. The disclosed ridge vents may incorporate regions having relatively lower fiber density to allow air to ventilate efficiently and regions with higher fiber density to form moisture barriers, support structures, or other structures of the vents. Disclosed vents may have integral moisture barriers, alignment tabs, special contours for functional and aesthetic advantages, interlocking ends, solar panel integration, ambient light admittance, and other unique features representing enhancements and improvements over traditional Rotter style fiber mesh ridge vents. These and other aspects, features, and advantages of the disclosed ridge vent configurations will become more apparent upon review of the detailed description set forth below taken in conjunction with the accompanying drawing figures, which are briefly described as follows.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a mesh ridge vent having a central fold notch formed there to facilitate accurate folding of the ridge vent along its center line.

FIG. 2 is an end view of a mesh ridge vent having a central space flanked by mesh material.

FIG. 3 is a perspective view of a mesh ridge vent formed with lateral slots allowing the ridge vent to be used on metal roofs having standing seams.

FIG. 4 is a perspective view of a mesh ridge vent with an upper surface contoured to resemble ridge cap shingles.

FIG. 5 is an end view of a mesh ridge vent having relatively more dense edges and a relatively less dense central portion.

FIG. 6 is a perspective view of a mesh ridge vent with an upper surface contoured to receive ridge cap shingles.

FIG. 7 is a perspective view of a mesh ridge vent having a depending tab sized to fit into a ridge slot to align and secure the ridge vent.

FIG. 8 is a perspective view of a mesh ridge vent having depending tabs sized to fit into a ridge slot and to accommodate a ridge beam.

FIG. 9 is a perspective view of a mesh ridge vent contoured to form outboard wind baffles.

FIG. 10 is a perspective view of a section of mesh ridge vent contoured on its ends to interface with like ridge vent sections.

FIG. 11 is a side elevational view of two sections of the mesh ridge vent of FIG. 10 joined together at their ends.

FIG. 12 is a side elevational view of two mesh ridge vent sections joined at their ends with alternate interlocking end configurations.

FIG. 13 is a perspective view of a mesh ridge vent with exposed solar energy collectors arrayed along its upper surface.

FIG. 14 is a perspective view of a mesh ridge vent formed with openings for admitting light that may then be directed into a home.

FIG. 15 is a perspective view of a roof deck mat made of mesh material for ventilating and cooling a roof deck.

FIG. 16 is a perspective view of an alternate embodiment of a roof deck mat made of mesh material for ventilating and cooling a roof deck.

DETAILED DESCRIPTION

Reference will now be made in more detail to the drawing figures, which illustrate a variety of ridge vent and deck cover configurations according to the invention. The disclosed products incorporate air permeable portions formed from a sheet, strip, or mat constructed of randomly aligned synthetic fibers that are open and blended; randomly aligned into a web by airflow, air-laid techniques, needling techniques, or other means; joined by phenolic or latex binding agents; and heat cured to produce an air-permeable mat. Such a mat is disclosed in U.S. Pat. No. 5,167,579 of Rotter entitled Roof Vent of Synthetic Fiber Matting. This patent is hereby incorporated fully by reference. The terms mat, mesh, fibrous mesh, and similar terms may be used throughout this disclosure to refer to air permeable fibrous mats.

The various ridge vents and deck cover configurations disclosed herein also contemplate a fibrous mat in which selected portions of the mat are formed with a relatively higher fiber density and other portions of the mat are formed with a relatively lower fiber density. Varying fiber density within fibrous mats can be achieved in a number of known ways such as through needling techniques and/or covering or exposing, as needed, classification apertures in the distribution devices of an air-laid system, or by the use of air streams, water jets, and the like to move fibers to desired locations before the binder is applied and/or cured. Regardless of the technique, the result can be a fibrous mat with higher fiber density in some portions of the mat and lower fiber density in other portions. Some of these fabrication techniques also can be used to create structures such as notches, channels, support features, wind baffles, and the like as a part of the fabrication process.

The term “moisture barrier” will be used in the detailed description below to refer to a layer or layers of material on or in a fibrous mat that are substantially impervious to water or moisture. This term should be understood to encompass any structure or structures that can be used to prevent penetration of water including, without limitation, a coating of water resistant material applied by spraying, rolling, calendaring, or otherwise onto a fibrous mat; a membrane attached, affixed, bonded, or adhered to the fibrous mat; a layer of high fiber density on or in the mat; a layer of fibers containing sufficient amounts of resins to close the spaces between the fibers; a water impervious mat of fibers adhered or otherwise fixed to an underlying air permeable fibrous mat; and any other structure or material that forms a barrier to the entry of moisture. For the sake of clarity and brevity, the term “moisture barrier” when used below is intended to encompass any and all of these structures, materials, and techniques for substantially preventing the passage of water and moisture, whether used alternatively or in combination with each other.

FIG. 1 illustrates a ridge vent 21 comprising an air permeable mat 22 having a moisture barrier 26 forming the top or exposed surface of the ridge vent. A longitudinally extending notch 28 is formed in the mat 22 extending generally along the centerline of the ridge vent 21. The notch 28 is generally V-shaped in the illustrated embodiment, but may be of any other useful shape as needed. The notch 28 divides the mat 22 into first and second sections 23 on either side of the notch. The notch 28 facilitates the bending of the ridge vent 21 along its center line for installation along the ridge of a roof covering a ridge slot. The notch 28 can be formed by cutting the mat during fabrication, by attaching the first and second sections 23 to the moisture barrier 26 as separate pieces, or by modifying the needling or air-laying process or using air or fluid jets to displace fibers during fabrication so that fibers are not present in the area of the notch.

FIG. 2 is a lateral cross sectional view of a ridge vent 31 having a moisture barrier 32 and a pair of fiber mesh strips 34 and 36 depending therefrom. An open gap 37 is defined between the mesh strips and this open gap overlies a ridge slot when the ridge vent 31 is installed along the ridge of a roof. The mesh strips 34 and 36 may be attached to the moisture barrier 32 by any appropriate means such as, for example, a peel-and-stick membrane 33 as shown in the illustrated embodiment. If the moisture barrier 32 is a layer of dense fibers, it may be adhered with adhesive or may be formed as a unitary layer during the air-laid or other process used to fabricate the ridge vent 31.

FIG. 3 is a perspective view of a ridge vent 41 having a moisture barrier 42 and a pair of mesh strips 44 and 46 depending from the edge portions of the moisture barrier. An open gap is formed between the mesh strips 44 and 46 as in the embodiment of FIG. 2 and overlies a ridge slot when the ridge vent 41 is installed. Laterally extending depressions or notches 47 are formed in the mesh strips 44 and 46. In this embodiment, the lateral notches are generally curved in shape, but this is not a limitation and they may be otherwise configured. The ridge vent 41 is configured to be installed along the ridge of a tin or metal roof having upstanding ridges or standing seams. The laterally extending notches 47 are spaced, sized, and configured to fit over and rest against the ridges or standing seams to form a barrier against windblown rain and vermin. In the illustrated example, the moisture barrier 42 is formed of a layer of dense fibers and binders that prevent penetration of water.

FIG. 4 is a perspective view of a ridge vent 51 formed of an air permeable fiber mesh material 52. The mesh material 52 is shaped on its underside during the fabrication process to define a pair of depending legs separated by a gap 53. The gap 53 overlies a ridge slot when the ridge vent 51 is installed along the ridge of a roof. The upper side of the mesh material 52 is formed during fabrication to define a series of sloped lands 56 and risers 57. The lands 56 are covered with a moisture barrier 55, but the mesh material 52 is left exposed on the risers 57. When the ridge vent 51 is installed along the ridge of a roof, the gap 53 overlies a ridge slot formed along the ridge and the lands and risers mimic the look of ridge cap shingles installed along the ridge. Thus, ridge cap shingles need not be installed atop the ridge vent as is the case with traditional mesh ridge vents; although ridge cap shingles may be installed. If installed, one edge of each ridge cap shingle preferably overhangs the riser of its land to help shield the riser from windblown rain and the like. Further, heated air from the attic space below can rise through convection into the gap 53 from where it can vent to ambience both laterally along the edges of the ridge vent and longitudinally through the risers 57 of the ridge vent, as indicated by the arrows in FIG. 4. Improved ventilation and appearance are thus aspects of the ridge vent configuration of FIG. 4.

FIG. 5 is a lateral cross section of a ridge vent 61 of another configuration. The ridge vent 61 has a moisture barrier 67 from which a fiber mesh mat 62 depends. The mesh mat 62 is continuous across the width of the ridge vent, but is formed during fabrication with a relatively less dense central portion 63 and relatively more dense edge portions 64. The relatively less dense central portion 63 is less resistant to the flow of hot air from an attic space below while the relatively more dense portions 64 allow the air to escape to ambience while preventing windblown rain and insects from entering the attic through the ridge vent. As described above, the different fiber densities of the mesh mat 62 may be formed through any of a variety of techniques including needling techniques, air-laid techniques, blowing techniques, or combinations thereof.

FIG. 6 is a perspective view of a ridge vent 71 that embodies principles of the invention disclosed herein in yet another configuration. The ridge vent 71 comprises a mesh mat 72 that is shaped and configured during fabrication to define on its underside a gap 73 flanked by a pair of depending edges portions. When installed, the gap 73 overlies a ridge slot formed along the ridge of a roof and the depending edge portions rest on the shingles of the roof to each side of the ridge slot. The upper surface of the mesh mat 72 is formed to define a series of sloped lands 77 that extend to exposed edge portions 78. A slot 79 is formed between the edge portion 78 of each land and the top surface of the next land. The exposed surfaces of the lands 77 may have a moisture barrier 76 formed on or fixed thereto, but such a moisture barrier is not a requirement. During installation, the ridge vent 71 is rolled out along the ridge of a roof and positioned such that the gap 73 overlies a ridge slot formed along the roof ridge. The ridge vent 71 can then be attached to the roof deck with fasteners driven through the edge portions of the vent and into the roof deck below. Ridge cap shingles can be installed by sliding each ridge cap shingle into a corresponding slot 79, temporarily bending back the overlying edge portion 78, and installing roofing nails through the ridge cap shingle and into the roof deck below. The edge portion can then be laid back down to overlie the edge of the ridge cap shingle and hide the nails with which the ridge cap shingle was installed.

FIG. 7 illustrates a contoured ridge vent of another configuration according to aspects of the disclosure. The ridge vent 81 comprises a moisture barrier 82 from which a fiber mesh mat 83 depends. The mesh mat 83 is contoured during fabrication to define air permeable edge portions 84 and 85 and a depending central plug 86. If desired, the central plug may comprise a region of relatively lower fiber density and the edge portions may comprise regions of relatively higher fiber density. The central plug 86 is sized to extend into a ridge slot formed along the ridge of a roof when the ridge vent 81 is installed along the ridge. In this way, the central plug fills the ridge slot and insures that the ridge vent 81 is properly positioned and centered along the ridge of a roof. The configuration of FIG. 7 is designed to be used with a roof structure that does not include a central ridge beam. FIG. 8, on the other hand, represents the same concept for use with a roof structure having a central ridge beam extending beneath its ridge. More specifically, a gap 99 is formed along the depending plug of the fiber mesh mat and this gap fits over the central ridge beam below when the plug is extended onto a ridge slot.

FIG. 9 illustrates a ridge vent of yet another configuration embodying aspects of the invention. The ridge vent 101 comprises a moisture barrier 102 forming an upper surface of a mesh mat 103. The mat 103 is formed during fabrication to define a pair of upstanding wind baffles 104 and 106 along its outboard edges. Edge portions of the air permeable mat 103 are exposed just inboard of the wind baffles and heated attic air can escape from an attic below through these exposed edge portions, as indicated by the arrow in FIG. 9. The wind baffles 104 and 106 can be formed by any of the methods discussed above and, as known in the art, help to draw air out of the attic by creating vortices during a breeze. The wind baffles 104 and 106 may comprise regions of relatively high fiber density while the remainder of the mat 103 may comprise a region of relatively low fiber density, also accomplished through any of the fabrication techniques discussed above.

FIG. 10 illustrates another ridge vent that embodies aspects of the invention. Many mesh-type ridge vents in the market are stored and shipped in spiral rolls of long sections of vent. However, there are some advantages to ridge vents made in relatively short sections of, for example, 4 feet, which are shipped stacked atop one another in boxes. Molded plastic ridge vents generally are formed in such short sections and stacked for shipment. FIG. 10 shows an embodiment of a mesh-type ridge vent that is made in relatively short sections that can be shipped in stacked configurations rather than in rolled configurations. The ridge vent section 111, which may be about 4 feet long, comprises a mesh mat 110 topped by a substantially impervious moisture barrier 112. A first end 113 of the ridge vent section is formed with an upwardly facing rabbet and a second end 114 of the ridge vent section is formed with a downwardly facing rabbet. These rabbets facilitate the joining of like ridge vent sections end-to-end along the ridge of a roof. More specifically, as shown in FIG. 11, when two ridge vent sections are joined at their ends, the downwardly facing rabbet 114 of one section meshes with the upwardly facing rabbet 113(a) of the other ridge vent section. This forms a shiplap joint 116 between the two sections. Caulk or other adhesive may be applied to the surfaces of the rabbets to join the two ridge vent sections together with a moisture resistant joint.

FIG. 12 illustrates a ridge vent configuration similar to that of FIGS. 10 and 11. Here, however, rather than rabbets, one end of each ridge vent is formed with an upwardly facing interlock having a ridge and a trough and the other end is formed with a downwardly facing interlock having a complementary ridge and trough. When two ridge vents are joined together end-to-end, the ridge of the upwardly facing interlock nestles within the trough of the downwardly facing interlock as indicated with reference numeral 119 in FIG. 12. At the same time, the ridge of the downwardly facing interlock nestles within the trough of the upwardly facing interlock as indicated with reference numeral 120 in FIG. 12. This forms a more secure and better aligned joint between the two ridge vent sections. Caulking or adhesive may be used to secure the joint if desired, and the ridges and troughs improve the moisture penetration resistance of the joint.

FIG. 13 illustrates a ridge vent embodying another aspect of the invention exemplified herein. The ridge vent 121 comprises a fiber mesh mat 122 with a moisture barrier 123 formed on the upper surface. The mesh mat 122 may have differing fiber densities as discussed above or may be configured or otherwise shaped in any way such as those ways discussed above. An array of solar energy collectors such as solar cells 124 is disposed along the upper exposed surface of the ridge vent 121 for collecting energy from the sun and converting that energy to electrical energy. The solar cells 124 may be electrically coupled together with an appropriate wiring grid contained within the moisture barrier of the ridge vent and connections may be provided for electrically coupling a length of solar ridge vent to a main electrical grid of a building. Solar cells may be applied to only one half of the ridge vent 121 for installations where a roof ridge extends east-to-west and only one side receives sunlight. Alternatively, solar cells may be applied to each side of the ridge vent 121 for installations where a roof ridge extends north-to-south or is otherwise oriented so that both sides of the ridge vent receive sunlight.

FIG. 14 illustrates another ridge vent configuration according to aspects of the invention. The ridge vent 131 includes an air permeable fiber mesh mat 132 having a moisture barrier 133 formed on or attached to the upper surface thereof. The mat in the drawing is of uniform thickness, but may be formed in any configuration with or without varying density, as described above. Arrays of windows 134 are formed in the ridge vent 131 and communicate therethrough. The windows 134 are rectangular in the illustrated embodiment, but may be formed with other shapes as needed or desired. The windows 134 function to reduce the weight of the ridge vent 131 while not interfering with the ventilation properties of the vent. Further, the windows admit light through the ridge vent. This light can be captured beneath the ridge vent and directed to the inside of a home or other structure using known devices such as light tunnels or fiber optic lighting systems. A transparent or translucent ridge cap or cover may be applied to the top of the ridge vent 131 to prevent water penetration if desired or transparent panes may be mounted in the windows for similar purposes.

FIG. 15 illustrates a manifestation of the invention that is not a ridge vent, but rather a ventilating roof cover to be installed between a roof deck and roof shingles. The roof cover 141 includes a fiber mesh mat 143 having a moisture barrier 142 formed on, attached to, or otherwise incorporated on its upper surface. The mesh mat 143 is formed or configured with a series of ventilation channels 144 that extend from a lower portion of a roof deck to an upper portion of the roof deck when the roof cover is installed as shown in FIG. 15. The roof cover is then covered with roof shingles in the traditional manner. As the roof shingles heat in the sun, the heat is transferred to the air within the ventilation channels. This causes the air to flow by convection toward the upper portion of the roof, where it can be expelled to ambience as indicated by the upper arrow in FIG. 15. This, in turn, draws cool air into the ventilation channels from the lower portion of the roof as indicated by the lower arrow in FIG. 15. The result is that the roof deck is continually ventilated and cooled, the shingles are maintained at a lower temperature in hot sun, and less heat is transferred to the attic space below. The fiber density of the mesh of the roof cover is selected so that the mat supports the weight of the shingles above and withstands installation of the shingles.

FIG. 16 is an alternate embodiment of a roof cover for ventilation of a roof deck exposed to the sun. The roof cover 151 includes a fiber mesh mat 153 that is formed with regions 154 having higher fiber density and regions 156 having lower fiber density. The mesh mat 153 may have a moisture barrier on its upper surface. The roof cover of FIG. 16 functions in a manner similar to that of FIG. 15, except that instead of ventilation channels, the mesh mat has regions of lower fiber density extending from a lower portion of the roof to an upper portion of the roof. The regions of higher fiber density support the roof cover and weight of shingles above while the regions of lower fiber density allow for the relatively free flow of ventilation air beneath the roof cover as indicated by the arrows in FIG. 16.

The invention has been described herein in terms of preferred embodiments and methodologies considered by the inventors to represent the best modes of carrying out the invention. It will be understood by the skilled artisan; however, that a wide range of additions, deletions, and modifications, both subtle and gross, may be made to the illustrated and exemplary embodiments without departing from the spirit and scope of the invention set forth in the claims. 

What is claimed is:
 1. A ridge vent comprising: an elongated moisture barrier having a central portion and opposed edge portions; a fibrous mat material depending from and extending along the length of the elongated moisture barrier; the fibrous mat material defining at least a first region of relatively lower resistance to the flow or air and at least a second region of relatively higher resistance to the flow of air; the at least one second region extending generally along at least one of the edge portions of the moisture barrier.
 2. The ridge vent of claim 1 wherein the moisture barrier comprises a coating.
 3. The ridge vent of claim 1 wherein the moisture barrier comprises a membrane.
 4. The ridge vent of claim 1 wherein the membrane comprises a layer of fibrous materials that is sufficiently dense to prevent penetration of water through the layer.
 5. The ridge vent of claim 1 wherein the first region comprises an air gap.
 6. The ridge vent of claim 5 wherein the air gap extends generally along the central portion of the moisture barrier.
 7. The ridge vent of claim 6 wherein the air gap is generally V-shaped to accommodate folding of the ridge vent along its central portion.
 8. The ridge vent of claim 1 wherein the at least one second region comprises a second region extending along one of the edge portions of the moisture barrier and another second region extending along the opposite edge portion of the moisture barrier, the first region being defined between the second regions.
 9. The ridge vent of claim 8 wherein the second regions are contoured.
 10. The ridge vent of claim 9 wherein the second regions are contoured to define spaced apart transversely extending notches.
 11. The ridge vent of claim 8 wherein the first region comprises an air gap.
 12. The ridge vent of claim 8 wherein the first region comprises a region of fibrous mat material having a density less than the density of the fibrous mat material in the second regions.
 13. The ridge vent of claim 1 wherein the moisture barrier is scalloped to mimic the look of ridge cap shingles.
 14. The ridge vent of claim 13 wherein each scallop has a land and a riser and wherein the riser is air permeable to provide ventilation through the risers.
 15. The ridge vent of claim 13 wherein each scallop has a land and a riser and further comprising an overhang extending outwardly from each land to form a gap with the next adjacent land, the gap sized to receive an edge of a ridge cap shingle.
 16. The ridge vent of claim 1 wherein the at least one first region is disposed beneath the elongated moisture barrier and the at least one second region is located outboard of at least one edge portion of the moisture barrier.
 17. The ridge vent of claim 16 wherein the at least one second region is contoured to define a wind baffle outboard of the edge portion of the moisture barrier.
 18. The ridge vent of claim 1 wherein the at least one first region projects downwardly from the moisture barrier a distance greater than the downward projection of the at least one second region to define a plug extending generally along the central portion of the moisture barrier, the plug configured to fit into a ridge slot.
 19. The ridge vent of claim 18 further comprising a longitudinal gap extending along the length of the plug to accommodate a ridge beam extending along the ridge slot.
 20. The ridge vent of claim in claim 1 further comprising solar energy collectors disposed on an upper side of the moisture barrier.
 21. The ridge vent of claim 1 further comprising windows extending through the moisture barrier and the mat material to admit light through the ridge vent to be directed to the interior of a building.
 22. A ridge vent comprising an upper layer that is substantially impermeable to water and a lower layer of an open weave mat material that permits a flow of air therethrough, the lower layer comprising a first region that is relatively less resistant to a flow of air and a second region that is relatively more resistant to a flow of air.
 23. A ridge vent as claimed in claim 22 wherein the lower layer has a contoured bottom surface.
 24. A ridge vent as claimed in claim 22 wherein the first region comprises a gap.
 25. A ridge vent as claimed in claim 22 wherein the first region comprises a less dense open weave mat material and the second region comprises a more dense open weave mat material.
 26. A ridge vent as claimed in claim 22 wherein the upper layer is contoured to resemble ridge cap shingles. 